


The Battle of Macragge, First Tyrannic Wars

by purplekitte



Series: Daemon Prince Guilliman AU [3]
Category: Warhammer 40.000
Genre: Alternate Universe - Canon Divergence, Chaos Ultramarines, Daemon Prince!Guilliman, Demon Summoning, Female Space Marines, Gen, Human Sacrifice, I love people thinking about magic methodically and scientifically, Worldbuilding, and using its symbology efficiently
Language: English
Status: Completed
Published: 2014-07-11
Updated: 2017-01-15
Packaged: 2018-02-22 19:21:12
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 3
Words: 3,332
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2518952
Author URL: https://archiveofourown.org/users/purplekitte/pseuds/purplekitte
Summary: <blockquote class="userstuff">
              <p>The tyranid menace bears down on the Realm of Ultramar, independent bastion of balance between the word of Daemon Prince Guilliman and the dark magic of the Ruinous Powers, order and chaos, good and evil.</p>
            </blockquote>





	1. Chapter 1

**Notes for the Chapter:**

> cross-posted from [tumblr](http://adepta-astarte.tumblr.com/post/91491122406/the-battle-of-macragge-first-tyrannic-wars)

The Great Devourer, the hive minds of which individuals tyranid creatures were as cells to a human body, drew in whirlpools of souls as easily as their bio-ships sucked up oceans. The xenobiologists, librarians, and warpsmiths who studied them theorised that as Chaos was the collective subconscious of the beings in this galaxy, tyranids were their own god. So fundamentally different was it in origin, it barely cast a shadow on the part of the Immaterium they were familiar with, the part that responded to beings of sentience and emotion in a way tyranids were not.

The downside to this was that Hive Fleet Behemoth was not throwing usable power into the Warp proportionate to the death and fear caused, which could have been used against it. It also disrupted communication and travel when they needed it the most.

The main bulk of the hive fleet made straight for Macragge, though it could be distracted by a juicy target along the way. The Imperium’s Ordo Xenos called this divine retribution, though the xenobiologists of Ultramar said they showed no factional preference for human flesh, and many of the splinter fleets that broke off were making due for Terra (a belief later supported by the behaviours of Hive Fleets Leviathan and Moloch).

It was the Pharos, drawing the bugs like a moth to a flame, or so the most likely theoretical went. They could turn it off, or have Sotha direct it somewhere other than Macragge, but then they’d be blind except for the distant light of Terra’s Astronomicon. Macragge was a high priority planet to protect for many reasons, but better it be threatened now than for the hive fleet to gain more power on worlds they couldn’t predict and couldn’t get to in time to save, and eventually devour everything including it.

They had won at Cold Steel Ridge, but at too great a cost. Spores still fell, and the void war continued above their heads where they were outnumbered and outgunned.

‘It must be done,’ Calgar told his command squad. He brushed off the efforts of the Apothecary trying to tend him. ‘We’ll return to the _Octavius_ and enact the ritual.’

‘It must be done first, here, Chapter Master,’ Librarian Tigurius advised firmly, cleaning his rail rifle. Traditionalists sniffed at weapon-patterns from their tau allies, but neither Tigurius nor Calgar held with that sort of hide-bound Imperialist-sounding talk, though Calgar would never swap for anything the Gauntlets of Ultramar that had been passed down for millennia.

‘Because?’

‘Connection to the ground of a planet, Macragge of all planets in particular, will enhance the ritual’s power. Also, the soul-net funnelling our dead away from the Great Devourer is most firmly centred around the Fortress of Hera where the Pharos focal point lies.’

‘Will it be enough?’ He was not afraid, but a plan likely to fail needed more contingencies than usual, ones he admittedly did not have enough of, nor could so many resources be wasted on it. This was his gamble, all of it. Not because he was reckless, but because he had to seize the one chance he saw for decisive victory as opposed to inevitable defeat. The might of the Ultramarines had convened, as well as that of many of their Successor Chapters from across the Realm, any who could be spared and make it in time. They were only a small empire and beset by enemies on all sides, not to mention already within their borders.

‘The gods are on our side. I have meditated on this every moment I’ve had. For all that they are rarely trustworthy or reliable allies, it hardly suits them either for us all to be eaten by tyranids, to provide them no more sustenance or amusement.’

‘How quickly can preparations be made?’

‘Young Calgar,’ drawled Chief Chaplain Ortan Cassius, ‘do you really think I wasn’t ready days ago?’

‘Then we have no more time to spare.’

In the olden days, and in disorganised and amateurish Chaos cults across the galaxy, ritual magic was a haphazard and inefficient thing. Ultramarines approached it systematically, with a diligence and strictly-controlled experimentation and pattern-seeking that their code-minded allies in the Cult of Mercury could only admire. They did not burn planet after planet to bring up a simple Warpstorm like undisciplined sorcerers fresh from the Eye of Terror. They knew how to wring every drop of power and metaphor out of the sacrifices they did make, how to channel ambient currents and natural phenomena. They were as far beyond moulding grimoires as the enginseers of a hydroelectric power plant were from primitive tribes warming themselves over an open fire.

For this daemonic summoning, only two blood sacrifices were needed here, in the summoning circle of perfectly positioned and angled laser grids with blood lines drawn under it, now, in person. This summoning hadn’t been done in centuries, in Calgar’s lifetime, but it was recorded and passed down with Ultramarine-exactness.

‘I take this deed upon myself and none other of my brotherhood,’ he intoned. ‘Though my soul be damned to the Ruinous Powers of the Warp forever, that price I gladly pay.’

The first sacrifice must be an Astartes of Guilliman’s gene-line and he must be willing. He must lay down his life without hesitation or reservation. They had many volunteers and Calgar chose from the most heavily wounded. It was always tragic to watch a good and worthy life cut short, but this was the easy one, the honourable one, a good and worthy death.

The other sacrifice had to be unwilling. That was what drove the power. Not only could they not have agreed to lay down their life, they had to fight all the way. If they came to peace with their death or its inevitability, if they sought meaning or grieved, the ritual would be invalid. The sacrifice must scream defiance to men and gods to the very last breath: I refuse to die, I’ll kill you all, I will break open hell because it could never contain me.

It took many tries until the magic resounded with the harmony of a worthy sacrifice.

Blood staining his hands, Calgar knelt in obedience and shame, but not regret.

He had read the reports passed down to him by previous Chapter Masters, but he had hoped it would look more human somewhere in his hearts. More like an Astartes than a daemon.

A finger lifted his chin, pricking him with claws? shadows? ‘I want you on your feet. I keep saying this “Regent of Ultramar” business makes you sound like the Imperium with _their_ father’s corpse.’

His eyes, Calgar thought. Though they glowed like blue searchlights, they were human. They were human because they were sad, so very sad. Looking into them, he could see, or perhaps imagine, through the shadow, to the being this once was: noble, great in war and in making war unnecessary, clad in ultramarine blue power-armour. The oldest reports about him sounded like poetry, unprofessionally so he’d always thought until now.

He looked up into the sky, seeing with more than mere eyes. ‘The Shadow in the Warp? Brief me on its nature, the tactical situation, and the theoreticals and practicals you’ve considered.’

‘Yes, my primarch.’


	2. Accompanying meta

**Notes for the Chapter:**

> cross-posted from [tumblr](http://adepta-astarte.tumblr.com/post/91491400116/a-bit-more-daemon-prince-guilliman-au)

Like in canon, Guilliman splits his Legion down into separate Chapters. While he didn’t have the Shadow Crusade to pound these ideas into him, he still sees the value of having small, scattered, independently operating forces across his Realm rather than depending on central leadership when travel and communication are difficult. While they’re less anti-psyker than the Imperium, their astropaths just aren’t as good without soul-binding, so communication across interstellar distances isn’t even as fast or reliable as in the Imperium. Each couple systems can have an Astartes Chapter looking after them and the Astartes can have their own homeplanet/domain to draw resources from and act out of without going through Macragge.

Back in the Imperium, the eight loyalist Legions never underwent reorganisation, among other parts of the infrastructure. Events like the Age of Apostasy, where a single person accumulates too much power and goes off the deep end with it with no one to put them down very a very long time, are much more common, however many checks and balances people try to institute after every time it does happen.

The Astartes Legions are known for their deep rivalries with each other and tumultuous relationships with the non-Astartes authorities. The Legion Masters of each Legion hold a place on the High Lords of Terra. Even when they’re not fighting each other, Legions just aren’t good at working together. Their combat doctrines, specialties, rank structures, everything just don’t go together and it takes a lot of effort to make it work, especially from men not used to anything approaching compromise. There are also more frequent problems with a bunch of assault squads showing up for a war and discovering they brought no devastators with heavy weapons, for instance.

Legions hardly concentrate in one place all at once, but they do have a central command structure that exists. On one hand it makes it easier to coordinate thousands of systems across an entire galaxy; on the other, it can make them unwieldy and slow to respond, especially if the distant high command and the Astartes on the ground have different ideas about what’s going on and what should be. Legions keep various bases outside their homeworld, but they tend to be more ramshackle and temporary than a proper and permanent fortress-monastery on a Chapter world that you’d see in canon and their infrastructure for supplying their fleets are more like those of a fleet-based Chapter. They take what they need from whatever worlds or forgeworlds they pass by when they need it, which causes a lot of headaches.

Sometimes individual warbands split off from the main force and stop listening to orders from their Legion Masters. These are generally tolerated because no one in their Legion or the Inquisition has time to hunt them all down as long as they don’t turn to Chaos or start recruiting. Such groups usually fight on their own in some corner of the galaxy until they die off. While recruits are periodically kidnapped off various feral worlds by various Legions because their homeworlds simply can’t keep up with demand, these aspirants are shipped back home, because total control over neophytes and the Space Marine creation process is considered very important to keeping the Legion unified and those in command in command. Messing with recruitment is a big deal and considered an outright act of treason, or anticipation of treason.

The Iron Hands are an exception to the usual centralisation, their clan companies always operating independently with only the most nominal of centralised high command. They do all send their aspirants back to Medusa for gene-seed implantation and education though.

Back in Ultramar, they have both their various Chapters and what they call independent strike forces. Though their very existence annoys the most as-the-good-Codex-says Marines, they exist/were specifically tasked in the Codex Astartes itself to not follow it, a legacy of Aeonid Thiel. They can be tactically unorthodox and dedicated to being unpredictable, they may be specialists in a particular type of warfare or specific threat (like Chaplain Cassius’ force of First Tyrannic War veterans in canon), they do things like field-testing new tau weapons or other experimental tech before their wider adoption across the Realm. Guilliman never intended to be inflexible, though that is a natural tendency of his gene-line unless they fight it.

Not all Astartes in the Realm of Ultramar are genetic descendents of Guilliman either. In the early days they took in stray squads or companies who just ended up with them for one reason or another in the whole mess and confusion of the Heresy. These forces were disorganised enough and rarely well-rounded fighting forces in one place at one time that they were integrated into the larger Ultramarine formations of the time. So these days you get Black Consuls or Doom Eagles who happen to have Mortarion or the Lion’s geneseed and no one knows this except maybe their Apothecary or if they have to do a gene-scan for the purposes of a few specific bits of ritual magic. A Chaplain may be teased about being a son of Lorgar or an artillery officer about Perturabo or a berserker about Angron.

More recent forces that swore to Ultramar, rogue companies fleeing the Imperium for instance, generally operate in separate Chapters, as long as they accept the Codex and the overlordship of the Regent of Ultramar out of Macragge, like everyone else does. They call themselves the Venom Thorns now, for instance, but they know their ancestors were once Imperial Fists, who had philosophical differences with the leadership, were granted a fief in Ultramar, and changed their name.

Another non-canonical addition to the Codex in this AU is death companies, somewhat similar to Blood Angel ones. Death companies consist of those with the various marks of Chaos (and associated Chaos Marine special troops like berserkers or plague marines), possessed Marines, and other specialised daemon summoners or mutants. Psykers aren’t necessarily in this company, but to be considered outside of it they have to be largely free of Chaos taint and confined to a limited list of acceptable psychic specialties/abilities. They can never be promoted to command positions outside this company or take part in governance of the Chapter world or other such duties. They are carefully watched over by Chaplains to make sure they’re not spreading Chaos bs to everyone else or going full yolo traitor against Ultramar or otherwise off the deep end even comparatively, which certainly happens. It is considered best that no individual member of the death company survives that long after being exiled to it for this reason.

There is a certain level of Chaos ritual sorcery a normal captain or Chapter master is expected to be familiar with, but not the highly specialised stuff nor are they supposed to use it except in limited situations detailed in the Codex. Ultramar is hardly free of Chapter going crazy and having to be declared Excommunicate Traitorous, but that’s just something that happens in life. There will always be someone summoning a daemon in the middle of one of your own cities where you didn’t want it, or your astropath or PDF sanctioned psyker getting possessed by a many-tentacles thing, and you just have to deal with it.


	3. Chapter 3

**Summary for the Chapter:**

> Marneus Calgar visits an old friend. [Calgar/OFC, WIP]

The village at the coordinates Calgar had been given has no landing pad, but there was so much nothing around it that a designated one was hardly necessary. ‘Avoid the sheep,’ he told his pilot.

Despite the lack of modern conveniences, only very small children were staring openly. They were not exactly feral worlders, so much as lacking industrialisation. Some part of him wondered why they didn’t want to better themselves, to innovate instead of using scraps of imported technology, but he supposed some people were happier wandering with their herds than living in a city, and living in small numbers on a world with few resources, the future the same as the past. The naked toddlers, too old to be carried in a sling by their mothers but too young to work were playing some sort of game on dataslates as new as could be found ten years ago on Konor.

The most solid building around, though still a portable structure, had a place of honour beside the bloodstone circle. It was obviously a forge from the smoke it was belching. Calgar needed to duck through the doorway in his armour, but he could stand up inside.

Pele was unarmoured, and for that matter wearing nothing but a leather skirt. That was hardly atypical among the locals, but a normal blacksmith would be wearing an apron, were she not a Space Marine. Or at least gloves; even knowing she didn’t strictly need them, some Ultramarine part of Calgar winced just on principle at why someone would do something so unnecessary and easily avoidable as stick her hands in open flame, but it was a Salamander affectation. The heat was by no means that of an industrial forge, but it was noticeable and she was hardly sweating.

Half-finished master-crafted stormbolters laid scattered around, covered in oiled cloth to keep sand from delicate, precisely calibrated inner workings. That was not what she was working on.

‘Nails?’

‘My apprentice is sick and if nails are needed today for the new sheep pen, they’re not going to wait for tomorrow and they’re not going to make themselves.’

‘A destroyer plague?’

‘A flu.’

A human apprentice then. He didn’t sigh, because it was just their way. When he’d once asked why she didn’t live at the fortress-monastery, she’d asked whatever would she do there? What would the point of spending time at home be? She could take the bike out back and be there in no time. She also taught the children reading and writing and such things; she, the noble Chapter Master of the Abyssal Flames.

‘My dear Marneus, if it were urgent, you wouldn’t have come in person. Let me finish and freshen up.’

‘My apologies.’ He backed from her tent and went to walk the perimeter of the town. He felt the warm feeling in his hearts just from seeing her. As Guilliman had written, everyone should have someone who made them feel safe, an advisor they could bear their soul to. He had other advisors and Chaplains and Chapter Masters, but he’d missed her personally. He was Regent of all Ultramar, but she was a dear friend he could let that drop around.

‘Auntie’s calling you to her tent, sir,’ a small girl told him as a chill began to fall and braziers were lit.

Her tent was the largest, that she could actually stand in it. Just now she was kneeling, adding charcoal to her brazier. He sat before her.

Her dark eyes were lined with gold paint that shined against her olive-brown skin. She wore a nicer cream skirt and still no shirt. She had added a significant amount of jewellery: gold bangles around her wrists and ankles, rings on fingers and toes, bands around her neck, chains tying her hair back in smooth oiled loops, and a wide pectoral of a winged ultima symbol above her heavy breasts.

‘I did not realise before now, but you’re clearly not from the same ethnic group as these people. You’re an islander, yet you live with the desert dwellers.’

He knew the planet Cractau had two distinct ethnic groups: those who wandered the desert of its one continent and those who lived in the long chains of volcanic islands. Both were very dark, but with distinct variations of skin tone and hair and features he could easily differentiate.

‘Have you ever,’ she said with a hint of a smile, ‘lived through a tropical monsoon season? I spent my whole childhood wanting to get off the boat. That’s why I became an Astartes.’

He smiled back. Thank the gods for that.

‘What weighs on your mind, Marneus?’

‘Can’t I find any excuse to see you for love of your company?’ he teased, but there was business he intended to discuss with her. ‘I would ask a favour of you as well, both your advice and your intervention. I require the Hammers of Ultramar and the Saffron Wardens for pushing back Imperial aggression in the northwest, the incursion into Khorne’s Reach, but you see the potential for conflict there.’

‘In that they get along like Iron Warriors and Imperial Fists? Naturally. You want me and my warriors along as a mediating influence, without seeming like you’re treating them like squabbling children who need babysat?’

‘Precisely. The only other force I can spare in the area are the Crimson Lotus, and I can barely trust them, let alone trust them with anyone else.’


End file.
